The invention relates to devices and methods for dispensing, including devices and methods for dispensing, administering, injecting and/or infusing a medicinal product, including injectable medicinal products, such as insulin or hormone preparations, in doses. The application claims the priority of German patent application No. 103 43 548.4, filed on Sep. 19, 2003 with the German Patent and Trademark Office.
Devices for dispensing, administering or injecting injectable products are well-known. Such devices may include a dosing means, some of which are restorable or resettable, but it may be difficult to restore the dosing means and, in some cases, it may not be possible at all.
EP 0 614 386 B1 describes a device in which a toothed rack which acts on a piston arranged in a container for the dosing product is only provided with teeth over a part of its circumference. The teeth of the toothed rack cooperate with opposing teeth in such a way that the toothed rack can be shifted in discrete increments for the purpose of delivering the product but is prevented from being simply retracted. In order to be restored, the toothed rack is formed such that the teeth and the opposing teeth are disengaged by rotating the toothed rack by 90° and the toothed rack can then be manually retracted and moved to a starting position for a new, dosed delivery. Restoring the driven member requires the user to perform a number of movements in coordination. This, however, can lead to problems for a user who is perhaps not familiar with handling a somewhat complex mechanism, and therefore restrict the range of application of the device.
A device for administering an injectable product in doses is known from DE 10 046 279 A1, belonging to the Applicant, wherein a restoring spiral spring is provided which is secured when tensioned and is coupled to a drive unit by a release and can cause a restoring movement of the drive unit towards its dosing starting position.